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LM3708/LM3709 Microprocessor Supervisory Circuits with Low Line Output, Manual Reset and Watchdog Timer
June 2002
LM3708/LM3709
Microprocessor Supervisory Circuits with Low Line
Output, Manual Reset and Watchdog Timer
General Description
The LM3708/LM3709 series of microprocessor supervisory circuits provide the maximum flexibility for monitoring power supplies and battery controlled functions in systems without backup batteries. The LM3708/LM3709 series are available in a 9-bump micro SMD package.
Built-in features include the following:
Reset: Reset is asserted during power-up, power-down, and brownout conditions. RESET is guaranteed down to VCC of 1.0V.
Manual Reset Input: An input that asserts reset when pulled low.
Low Line Output: This early power failure warning indicator goes low when the supply voltage drops to a value which is 2% higher than the reset threshold voltage.
Watchdog Timer: The WDI (Watchdog Input) monitors one of the µP’s output lines for activity. If no .